Management of dietary protein intake of the CRF patient represents a critical balance between providing adequate protein to meet nutritional requirements, and limiting protein intake in the hope of slowing or abating the progression of CRF. A number of studies have demonstrated that reduced dietary protein intake can slow the progression of chronic renal failure. Finding effective ways to increase nitrogen retention and decrease urinary nitrogen excretion may help CRF patients maintain a more positive nitrogen balance and lessen the nitrogen load on the kidneys for a given dietary protein intake. Our laboratory has demonstrated that in older men and women, the consequence of adherence to a low protein diet is an accommodation that results in decreased muscle mass, strength,and compromised immune function. We have also demonstrated that when healthy, free living older men and women consume a weight maintenance diet providing the RDA for protein of 0.8 g/kg-1/day-1 for 15 weeks they lose skeletal muscle mass. These data clearly indicate that elderly people have an increased need for dietary protein (compared to young people). Data has also demonstrated that progressive resistance exercise improves nitrogen balance in older healthy individuals as well as in patients with mild to moderate chronic renal failure.